Lantern-pinion.



Patented luly 9, l90l. P. L.; CLARK.

LANTEBN PININ.

(N6 Mahal.)

(Applcon led June '4, 1900.)

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' A TTOHNEY m: Noam men ou UNITED STATES PATENT OFFICE.

PERCIVAL LJCLARK, OF BRISTOL, CONNECTICUT, ASSGNOR TO EMMA F. CLARK, OF SAME PLACE.

LANTERNMPINION.

SPECIFICATION forming part 0f Letters Patent NO. 677,856, dated July 9, 1901.

Application filed June 4, 1900. Serial No. 18,962. (No model.)

To @ZZ 'whom it may concern:

Be it known that I, PERcIvAL L. CLARK, a citizen of the United States, residing at Bristol, in the county of Hartfordand State of Connecticut, have invented certain new and useful Improvements in Lantern-Pinions, of which the following is a specification.

The present invention relates to the manufacture of watch and clock movements, and more particularly to the manufacture of lantern-pinions employedin small-sized clockmovements.

A lantern-pinion comprises a staff, a collet or collets, and the leaves, which latter are small wires arranged concentrically and parallel to each other and to the staff.

These pinions have heretofore been made in a variety of ways, the collets being almost invariably drilled to form the apertures for the stad and leaves. The staff and leaves have been secured in the apertures in the, collets in a number of ways, as by staking, as it is called, which consists in partially closing the outer ends of the apertures after- It has also been the leaves are putin place. attempted to form the leaves with shoulders which fitted against the inner faces of the opposing collets, and in some instances solder has been employed to hold the leaves and collets together. By the processes mentioned, and, in fact, by all processes prior to the present invention, the manufacture of lanternpinions has been a very'expensive proceeding, and it has been absolutely impossible to manufacture lantern-pinions, particularly of the smaller sizes, of absolute accuracy and uniformity of construction, it being safe to say that no two pinions in a thousand would be identical. Furthermore, it has been impossible to manufacture lantern-pinions of as small a size as desired, except at such greatv cost as to render their use practically prohibitive, and consequently in small-sized clockmovements itis common to use solid pinions. The method most commonly employed in the manufacture of lantern-pinions is to form the apertures for the staff and leaves by drilling, the aperture for the staff first being drilled and the collet itted on the staff, after which the apertures for the leaves are drilled. This process requires the use of drills of extremely small size, which are very expensive to make and keep in good condition, and even when made by the highest-priced skilled mechanics vary to such an extent as to prohibit uniformity in work. Furthermore, even should the drills be accurately and uniformly constructed the work of drilling the apertures in the collets is still dependent upon the skill and care of the mechanic, and for various reasons, such as the lack ofcare and attention on the part of the mechanic or because of his physical condition, the apertures in the collets will not be placed uniformly therein. This variation in the drillingr of the apertures in the collets is one, although not the only, cause of the variation in the resulting pinions, so that, as hereinbefore stated, it is practically and absolntely impossible to produce small-sized lantern-pinions of absolute accuracy and uniformity, and it has been found to be absolutely impossible by the methods heretofore used to make a lantern-pinion of as small a size as is sometimes desired.

The object of the present invention is to improve the manufacture of lantern-pinions in such a manner that they can be quickly manufactured, the smaller sizes being almost as quickly produced as the larger, and to produce lantern-pinions of smaller size than it has been heretofore possible to make, and, most important of all, to produce such pinions of accurate and uniform construction, a result which, while Very much desired, has never heretofore been accomplished.

The present invention is illustrated in the accompanying drawings, in which, on a very much enlarged scale, is a lantern-pinion embodying the same, and in Which- Figure 1 shows in elevation the staff. Fig. 2 shows in plan view the disks comprising the collet. Fig. 3 shows in elevation one of the leaves. Fig. 4 shows in elevation the lanternpinion. Eig. 5 shows a sectional view through the pinion shown in Fig. il, and Fig. 6 shows a perspective view of said pinion.

Similar letters of reference will be employed throughout the specification and drawings to designate corresponding parts.

lhave illustrated in the drawings a lanternpinion embodying the present invention, and in which A represents the staff, B the collet,

and C the leaves, the staff and leaves being of the usual and ordinary construction.

It is essential that the collet B have sufcient thickness so that it may be rmly fixed upon the staff A and also afford a firm support for the leaves C, and it is therefore usual to form such collets of metal (usually brass) of a thickness greater than the diameter of the leaves, in most cases of thickness approximately tu'o or three times the diameter of the leaves.

In each collet B is formed a central aperture b, which receives the staff A, and a concentric series of apertures c to receive the ends of the leaves C.

As before stated, the usual method now employed in making these pinions is as follows: After stamping out the collets the central aperture is drilled and the collet secured upon the staff, usually by a driving lit, as it is called. Then the apertures for the leaves are drilled and the leaves painstakingly inserted one by one. The resulting pinion, as before stated, is by no means accurate, and uniformity of construction is an absolute impossibility. In order to produce such pinions cheaply and at the same time secure absolute uniformity of construction and produce lanternpinions of smaller size than has .heretofore been possible, I propose to punch the collets from sheet metal, preferably brass, the punch at the same time that it punches out the disks forming the collet also forming the holes for the staff and the leaves of the pinion. The collet of a lantern-pinion is usually twice as thick as the diameter of the staff and three times as thick as the diameter of the leaves, and as it is well known that it is practically a mechanical impossibility to punch a hole of less diameter than the thickness of the metal through the piece of metal I form the collets of my pinion as Will nouT appear.

The collets B are formed of a plurality of disks b', preferably three such disks being employed to form the collet, as shown clearly in the drawings. It will be noted that each disk is of such a thickness that the apertures for the leaves may be readily punched therein with equal facility with the aperture for the staff and that a collet of sufficient strength is secured by assembling several of such disks upon the staff, as clearly shown in the drawings. The method of assembling consists in placing the desired number of disks in the female die of the machine fitted for the purpose, the disks being so positioned as to have the apertures in alinement with each other. The staff and leaves are now placed in a templet and positioned with relation to the disks and by a single movement driven into their respective apertures, the entire group of leaves being driven into the disks forming the collet at a single operation.

In order to facilitate the easy and rapid positioning of the disks forming the collet with their apertures in alinement with each other without the exercise of any special care on the part of the workman, each disk is provided with a centering-point which coperates with a complementary centering-point in the female die of the machine tted for the purpose. This centering-point may be of any form which will secure the desired result, the preferred form being that shown in the drawings, which consists of a notch h2, formed in the periphery of each disk and which engages a correspondingly-shaped projection formed on the wall of the female die.

The pinion described is that shown, andhas but a single collet, with the leaves projecting from one side thereof; but it is obvious that two collects may be employed if desired.

The relative diameters of the apertures l) and c and the staff A and leaves C are such that the staiic and leaves are fitted in by a driving t, and no additional holding meansis necessary.

By punching the collets instead of drilling them I attain, first, absolute accuracy of construction; second, absolute uniformity of construction, and, third, a great reduction inthe cost of production.

Under the methods now used the most skilled workman can only drill, according to size, about one to two thousand pinions in a Working day, While by my method I can produce twenty thousand or more absolutely perfect pinions in the same time.

It has heretofore been impossible to produce a lantern-pinion of as small a size as desired except at such a cost as to practicallyT prohibit their use, while by my process pinions in which the collets are but fifteen one-hundredths of an inch in diameter and having leaves of thirteen one-thousandths of an inch in diameter can be made almost as cheaply as those of a larger size.

Having described my invention, I claim as new and desire to protect by Letters Patent of the United States-- l. A lantern pinion comprising a collet formed of a plurality of disks having registering apertures for the leaves, substantially as described.

2. A lanternpinion comprising a collet formed of a plurality of disks having registering apertures for the leaves of substantially the diameter of the leaves, and the leaves fitted in said apertures, substantially as described.

3. A lantern pinion comprising a collet formed o f a plurality of disks having the apertures for the leaves and each disk provided with a centering-point to enable them to be assembled with the apertures for the leaves in alinement, substantially as described.

In witness whereof I have signed my name to this specification in the presence of two subscribing witnesses.-

PERCIVAL L. CLARK.

Witnesses:

ROGER S. NEWELL, ALICE E. BROWN.

IOC 

